Prince RV-2H Differential Poppet Relief Valve, Cast Iron, 3000 psi, 30 gpm, 3/4" NPTF Relief pressure adjustable from 1,500 to 3,000 psi with a flow rate of 30 gpm 3/4" female NPT threaded inlet connection Painted cast iron valve body for corrosion resistance Fast opening valve for pressure spike protection 180 degrees F maximum temperature for use in high temperature applications